Doctors Conduct First-Of-Its-Kind Clinical Trial Using Stem Cells to Treat Heart Failure (4/24/2008)

In the continuation of a cutting-edge series of clinical trials researching the use of stem cells to treat heart disease, Miller School of Medicine physicians and scientists announced on Wednesday that for the first time a patient underwent a procedure that could hold the key to repairing damaged heart tissue, a potential life-saver for the millions of people suffering from heart failure.

The study's leader, Joshua M. Hare, M.D., F.A.C.C., the Miller School's chief of the Cardiovascular Division and director of the Interdisciplinary Stem Cell Institute, said following the patient's triple bypass surgery Monday, mesenchymal stem cells, or a placebo, were injected directly in the patient's heart.

The stem cells are taken from the patient's bone marrow and cultured at a UM laboratory. It is the first study funded by the National Institutes of Health Specialized Center for Cell Therapy.

"The implication for this kind of therapy are enormous when you consider that nearly five million Americans suffer from heart failure, and 500,000 new cases are diagnosed each year," said Hare. "We are very optimistic because we have experimental data that show very clearly the cells we are using do have the ability to turn into new heart muscle cells."

The groundbreaking Phase I/II clinical trial is a double-blind, placebo-controlled study, where patients will be randomized to either receive stem cells or the placebo.

"Everything went well and the patient is doing well," Si M. Pham, M.D., surgical director of heart and lung transplantation, said of Rodolfo Hernandez, the 56-year-old man who was given the injection after bypass surgery at Jackson Memorial Hospital on Monday.

The Miami patient is the first of 45 people to participate in the NIH-funded study being conducted at the UM Health System (UM Hospital and affiliates, the Miami VA Medical Center and Jackson Memorial) and the Johns Hopkins University. The enrolled participants will be divided into three groups of 15 and one group will receive the placebo. Of the remaining groups, one will receive a low-dose of their own mesynchymal stem cells and the other, a high dose of the cells.

To qualify for the study, a patient must have had a heart attack that resulted in damage to the heart and reduced pumping strength in the left ventricle, the main pumping chamber of the heart, and be undergoing heart bypass surgery.

Hare described Hernandez as a "typical individual who would benefit from this kind of therapy."

"He had suffered a previous heart attack and required bypass surgery for blocked vessels in his heart. This was an opportunity for us to treat his scar, in addition to giving him new blood flow to his heart to prevent the condition from getting worse," Hare said. "This is the kind of patient who develops symptoms of congestive heart failure and who also is at risk for a condition called cardiac sudden death where people suddenly drop dead in the course of their daily activities because of the scar in their heart."

There is much more follow-up to do but Hare envisions a bright future where the groundbreaking procedure could, for some very ill patients, negate the need for a heart transplant. "We really foresee the possibility - again it is just a possibility and we have a lot of work ahead of us -that we can replace injured heart tissue with normal heart tissue and, if that turns out to be the case, then we would be able to treat patients who would otherwise need a heart transplant," Hare said.

A major goal of the study is to also develop a safety profile, look at efficacy, and if successful, seek approval to move on to Phase III, a much larger study. In the current phase, patients will be followed for 18 months and will receive several examinations with a sophisticated MRI scanner able to produce images that will show if the injected cells resulted in the growth of new heart muscle.

At the April 16 news conference, Miller School Dean Pascal J. Goldschmidt, M.D., praised Hare and his team and the strong partnership between UM and Jackson. The Dean said rigorously monitored stem cell research was being undertaken in various areas of the Miller School, including at the Diabetes Research Institute, with an eye to bringing more breakthrough therapies to patients.

"What Dr. Hare and his team have done is bring the work that was done in laboratories to treat patients directly and that is phenomenal and an extremely important step in the right direction," Goldschmidt said. The research now "is in the area of heart failure and heart disease but it's opening the doors for multiple other opportunities."

For this trial, under the direction of Ian McNiece, Ph.D., professor of medicine and director of experimental and clinical cell-based therapies at the Interdisciplinary Stem Cell Institute, the mesenchymal cells were extracted from the patient's bone marrow, purified and amplified.

In a previous multicenter study, Hare infused donor mesenchymal cells into people who had recently had heart attacks. Those cells were given intravenously and the trials showed the cell patients had lower rates of side effects such as cardiac arrhythmias. They also showed significantly improved heart, lung, and global function, compared with patients not given the stem cells.

In the current heart failure study, Hare said lab tests have shown that by injecting the cells directly in the injured area of the heart, "they will stay in the injured area and work to heal the injured area" by transforming into the kind of cells the patient needs - such as new heart muscle cells.

Asked about risks, Hare said there is potential for inflammation and heart muscle damage but the study has shown the cells interact favorably with the immune system.

"One of the exciting things about this cell-based field, a lot of times we anticipate risks and find the opposite, that a risk we were worried about is actually treated by the cells."

Note: This story has been adapted from a news release issued by the University of Miami

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